Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Represents the exercise price as a percentage of the fair market value of a single share of common stock on the date of grant.

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Represents the number of shares originally approved (usually by shareholders and board of directors) for awards under the prior plan of equity based compensation transferred to the current plan.

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Represents the percentage of voting power in the entity's common stock required for a specified exercise price to be effective.

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ORDINARY SHARE AND SHARE INCENTIVE PLANS - Stock Incentive Plans - Additional Information (Details) - shares			12 Months Ended
	Jan. 04, 2016	Jul. 21, 2006	Dec. 31, 2019	Dec. 31, 2016
2017 Equity Incentive Plan
Stock Incentive Plans
Number of shares authorized				2,000,000
Vesting period			4 years
Number of ordinary shares available for issuance pursuant to future grants			2,003,580
Number of shares transferred from the prior plan			1,590,693	960,940
2017 Equity Incentive Plan \| Stock Options and Restricted Stock Units RSU
Stock Incentive Plans
Number of awards outstanding (in shares)			1,334,657
2006 Equity Incentive Plan
Stock Incentive Plans
Number of shares authorized		1,500,000
Number of awards outstanding (in shares)				2,042,798
Number of shares expired			1,590,693
Vesting period		4 years
Number of shares transferred from the prior plan				8,474,347
Number of additional shares authorized	1,500,000
2006 Equity Incentive Plan \| Employee and Directors Stock Options
Stock Incentive Plans
Expiration term				7 years
2006 Equity Incentive Plan \| Employee and Directors Stock Options \| Minimum
Stock Incentive Plans
Exercise price as a percentage of the fair market value of an ordinary share on the date of grant				100.00%
2006 Equity Incentive Plan \| Employee and Directors Stock Options \| Maximum
Stock Incentive Plans
Percentage of voting power required of the company's stock for specified exercise price				110.00%
2006 Equity Incentive Plan \| Incentive Stock Option
Stock Incentive Plans
Percentage of voting power required of the company's stock for specified vesting period				10.00%
Expiration term				5 years